Machine for drawing out threads from tissues



'June' 22 1926.

H. C. FISCHER MACHINE FOR DRAWING OUT THREADS FROM TISSUES Filed Feb. 8,1926 3 Sheets-Sheet l i Z w June 22 ,1926. 1,589,524

H. C. FISCHER MACHINE FOR DRAWING OUT THREADS FROM TISSUES Filed Feb. 8,1926 3 Sheets-Sheet 2 June 22 1926. 1,589,524

H. c. FISCHER MACHINE FOR DRAWING OUT THREADS FROM TISSUES Filed Feb. 8,1926 5 Sheets-sheaf 3 Patented June 22, 1926 i UNITED STATES PATENToFricE.

HERMANN CHRISTIAN'FISCHER, or VIENNA, AUSTRIA, Assrenon TO THE FIRM?D'URKOPPWERKEAKTIEN-GESELLSCHAFT, or BIELEFIELD, GERMANY.

MACHINE FOR DRAWING OUT THREADSFROM TISSUES.

Application filed February 8, 1926, Serial No. 86,910, and in GermanyJanuary'15, 1925.

Machines for drawing-out threads from tissues are known heretofore, inwhich an up and down movable draw-out needle acts in such a way with acut-off device arranged underneath the same that the threads drawn-outfrom the tissue are cutoil. Said known machines have the drawback thatthey do not work reliably and that they cannot be used for all kinds oftissues, because the tissue was not satisfactorily stretched independence upon the working of the cutter.

To overcome said drawback, accordingto the present invention, besidesthe pressurefeet forcing the tissue against the feed contrivance, aseparate pressure-foot is arranged,.which co-acts independently fromsaid pressure-feet with the counter-cutter, while means are provided forcontrolling the counter-cutter and said pressure-foot in such a way thatthey are approached to one another at the moment of cutting whereby anincreased stretching of the tissue is attained.

The accompanying drawings illustrate the improved arrangement:

Figs. 1 and 2 are respectively a front view and a side view of a machinefitted therewith,

Fig. 3 is a side view of the cutter casing,

Figs. 4 and 5 are respectively a longitudinal section through and anelevation of the mounting of the cutter shaft in the cutter casing,

Fig. 6 is a sectional detail of Fig. 1 showing the arrangement of thepressure-feet,

Fig. 7 is a plan view of the cutters, and

Fig. 8 showsthe control for the separate pressure-foot.

The head 1 of the machineframe 2 carries the up and down movableneedle-bar 3 in a way known in the art, the draw-out needle 4 beingfixed to thelower end of said bar. Driving is effected from the wheel 5by the shaft 6. By a suitable transmission-gear, the shaft 6 drives bymeans of the feed-Wheel 7 the toothed-wheels 8 and 9 which are in gearwithethe toothed-wheels 10 and 11 of the feed-wheels 12 and 13 for theadvance of the tissue. Pressurefeet 15 arranged on the pressure-bar. '14and up and down movable-by meansof the latter, serve for'pressing thetissue against the feed-wheels 12, 13, the pressure-feet heads 16 beingin yielding contact with said feed-wheels. Between the feed-wheels 12,13 and on guide-bars 17 a casing 18 is slidable in vertical direction(Fig. 3). In the open top end of said casing a counter-cutter 19 isyieldingly mounted and fitted with guide-arms l9 laterally bounding thecutting-edge 19 (Fig. 7), while on a shaft 20 a crank-arm 21 is fixed,which projects into said casing and the outer end of which serves forthe reception of the cutter 22 (Fig. 2). At its underside the casing 18bears yieldingly upon a buffer-bolt 24 ar. ranged inthe bracket 23 whichcarries the guide-bars 17 said bolt beingso acted upon by an eccentric26 (Figs. 1 and 2) driven from the driving-gear by. means of aconnection-rod 25, that the casing is yieldingly lifted at the moment ofthe cutting ofthe thread presented by the needle 4. The counter-cutter19- is of a suitable archedformation corresponding to the casin 18 andso arranged that the cutter, 22, w ich bears from below against thecounter-cutter 19, lifts the same in such a way that the higheststretching of the tissue takes place at the cutting place. To ensure areliable engagement between the two cutters 19 and 22, the cutter 22 isat its front end fitted with guide-pieces 27 (Fig. 7).

Above the counter-cutter 19 and on a guide-bar 28 in themachine head 1,a pressure-foot 29 is arranged, the lower end on the guide-bar 28, thetension of which springs can be adjusted to suit the nature of thetissue treated. A control lever 33 engaging loosely between saidsprings, serves to move the pressure-foot by means of a cam-groove 34:in a control-cam 35 keyed on the shaft 6 (Fig. 8) in such a way thatwith lowered needle the pressurefoot 29 bears yieldingly upon thecountercutter 19, while at the moment of cutting the spring 32 istensioned by downward movement of the control lever 33 and thus thepressure of the pressure-foot29 upon the counter-cutter 19 is increased,whereas after completed cutting the pressure-foot 29 is slightly raisedfrom the counter-cutter 19 by the upward movement of the control lever33 and consequent tensioning of the spring 31, so that the further feedof the tissue can unobstructedly take place.

To permit always an exact adjustment of the cutter and a variation ofthe stretching height of the counter-cutter, the cutter shaft 20 ismounted in asleeve 36 (Figs. a and 5), which is loosely arranged inanother sleeve 37 and secured therein against axial displacement, whileit is pressed by means of springs 38, 38 against oppositely directedwedge faces 39, 40 of screws 4:1 in said outer.

sleeve 37. By adjusting said screws in the sleeve 37 the inner sleeve 36can be exactly adjusted to its required position of height. The cuttershaft 20 is driven by articulated cranks 42,43 (Fig. '1) of a crank-discLA on the lower driving-gear shaft in a way known in connection withsewing machines.

After completed feed of the tissue by means of the feed-wheels 12, 13,the descending needle 4 passes through the tissue and the threads areled downwards through the counter-cutter 19, the pressure-foot 29bearing then with its arms 30 yieldingly upon the counter-cutter 19,whereby the tissue is secured in position. By the then upwardly movingcutter 22 the counter-cutter 19, which is yieldingly mounted in thecasing 18, is raised and thereby pressed against the oblique ends ofthearms 30 of the pressurefoot 29. At the same time, the spring 32 on theguide-bar 28 of the pressure-foot 29 is tensioned by the descendingcontrol lever 33 and thereby the pressure-foot 29 isalso tensioned. Bythis co-action of the counter-cutter 19 and pressure-foot 29 and by thewedgelike action of the arms of the latter, the tissue is stretched overthe counter-cutter with increased pressure, so that a displacement ofthe tissue at the moment of cutting cannot take place. At the same time,by action of the eccentric 26 the casing is lifted, whereby theelasticity is increased and an absolutely reliable cutting of thethreads and guiding of the tissue is attained. After com pleted cutting,the pressure-foot 29 is released bv retraction of the control lever 33,

while the counter-cutter moves back, so than the succeeding feed of thetissue is not impeded.

The particular advantages of 'the improved arrangement consist in theprovision of a separate pressure-foot co-acting with the counter-cutter,whereby an absolutely reliable stretching of the tissue is'attained bothduring the passage of the needle therethrough and during .the cutting ofthe threads, while besides by reason of the arched formation of thecounter-cutter the highest stretching of the tissue takes place at themoment of cutting and at the cutting place.

\Vhat I claim, is:

1. The combination, in a 7 machine for drawing-out threads from tissues,of a feedgear for advancing the tissue, pressure-feet 7 -85 to ensurethecontact between said feed-gear and the tissue, -a cut-off devicecomprising a cutter and a counter-cutter, a separate pressure-footco-acting with said countercutter independently from said pressure-feet,and means to approach said counter-cutter and said oressure-foot to oneanother at the moment of cutting, substantiallyv as set forth.

2. An arrangement as specified in-claim 1, in which said counter-cutterand said pressure-foot are yieldingly arranged, substan-v tially as setforth. v

3. In an arrangement as specified in claim 1, a casing for the receptionof said cut-off device and mounted to yield in a vertical directionbetween said feed-gear, substantially as set forth.

1. In an arrangement as specified in claim 1, a casing for the receptionof said cut-oft device and mounted to yield in a vertical directionbetween said feed-gear, and means to impart to said pressure-foot and tosaid casing an additional tension at the moment when said cutter arivesat its cutting position, substantially as set forth.

5. An arrangement as specified in claim 1, in which said pressure-footis at its end divided into two members with wedge-shaped extremitiesengaging over said counter-cutter, substantially as set forth.

6. An arrangement as specified in claim 1, in which said counter-cutteris of arched formation, substantially as set forth.

7. In an arrangement as specified in claim 1, a casing for the receptionof said cut-ofi' device mounted to yield in a vertical direction betweensaid feed-gear, and a shaft for said cutter mounted in said casing andadjustable with reference to said counter-cutter, substantially as setforth.

8. In an arrangement as specified in claim 1, a casing for the receptionof said cut-off device mounted to'yield in a vertical direction betweensaid feed-gear, and consisting of an outer sleeve and an inner sleeveyieldingly and adjustably mounted in the latter, 1, guide-arms at thefront end of said counand a shaft for said cutter mounted in saidter-cutter and laterally bounding the cutinner sleeve, substantially asset forth. ting-edge of the latter, substantially as set 10 9. In anarrangement as specified in claim forth. 5 1, guide-pieces at the frontend of said cut- In testimony whereof I have hereunto set tor,substantially as set forth. my hand.

10. In an arrangement as specified in claim HERMANN CHRISTIAN FISCHER.

